Fashions. What do they mean?

It is often said almost with passive resignation 

that fashions reflect the customs of a people. 

But it would be more exact and much more useful to say 

that they express the decision and moral direction that a nation intends to take: 

either to be shipwrecked in licentiousness 

or maintain itself at the level to which it has been raised by 

religion and civilization. 

Pope Pius XII